EP0753668B1 - Dämpfer für ein hydraulisches pilotventil - Google Patents

Dämpfer für ein hydraulisches pilotventil Download PDF

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Publication number
EP0753668B1
EP0753668B1 EP94927797A EP94927797A EP0753668B1 EP 0753668 B1 EP0753668 B1 EP 0753668B1 EP 94927797 A EP94927797 A EP 94927797A EP 94927797 A EP94927797 A EP 94927797A EP 0753668 B1 EP0753668 B1 EP 0753668B1
Authority
EP
European Patent Office
Prior art keywords
piston
rotational shaft
case
pilot valve
hydraulic pilot
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP94927797A
Other languages
English (en)
French (fr)
Other versions
EP0753668A1 (de
EP0753668A4 (de
Inventor
Masayoshi Kawasaki Factory of Kabushiki MOTOTANI
Seita Kawasaki Factory Kabushiki Kaisha HAYASHI
Jun Kawasaki Factory Kabushiki Kaisha MARUYAMA
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Komatsu Ltd
Original Assignee
Komatsu Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Komatsu Ltd filed Critical Komatsu Ltd
Publication of EP0753668A1 publication Critical patent/EP0753668A1/de
Publication of EP0753668A4 publication Critical patent/EP0753668A4/de
Application granted granted Critical
Publication of EP0753668B1 publication Critical patent/EP0753668B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
    • F15B13/042—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
    • F15B13/042—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure
    • F15B13/0422—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure with manually-operated pilot valves, e.g. joysticks
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K31/00—Actuating devices; Operating means; Releasing devices
    • F16K31/44—Mechanical actuating means
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8593—Systems
    • Y10T137/87056—With selective motion for plural valve actuator
    • Y10T137/87064—Oppositely movable cam surfaces
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8593—Systems
    • Y10T137/87169—Supply and exhaust
    • Y10T137/87233—Biased exhaust valve

Definitions

  • the present invention relates to a hydraulic pilot valve having the features cited in the preamble of claim 1.
  • a hydraulic pilot valve of this type disclosed in JP 3-105 787 comprises actuating arms for operating spools of the pressure reducing valves.
  • a bracket branches off said actuating arms and is connected to a damper mechanism provided outside said valve body.
  • JP 58-176 169 discloses a hydraulic pilot valve for a travelling circuit for a power shovel of a construction machine.
  • a main shaft of said valve connected to an operation member is extended beyond the valve body and comprises a piston being movable within a separate casing filled with fluid.
  • the piston has an opening connecting two fluid filled chambers on the sides of said piston for producing a damper function upon an axial movement of said shaft.
  • a hydraulic pilot valve for a travelling circuit for a power shovel or the like is mounted to an under surface of a floor plate of a driver's cab and an operator sit on a seat disposed on the floor plate operates the hydraulic pilot valve. Accordingly, in order for the operator to easily handle the hydraulic pilot valve, it is necessary to locate a considerably long handling member.
  • the above defect may be eliminated.
  • the structure utilizes the hydraulic operating oil
  • viscosity of the hydraulic operating oil largely varies in accordance with a temperature thereof and it is difficult to obtain a stable damper effect. That is, in a case where the temperature of the hydraulic operating oil is low and the viscosity thereof is high, vibration attenuating effect to the handling member is large, whereas in a case where the temperature of the hydraulic operating oil is high and the viscosity thereof is low, vibration attenuating effect to the handling member is small.
  • the damper adapted to apply an operational resistance to the operation member is arranged in the valve body, the whole structure of the hydraulic pilot valve is itself made compact and an area for setting the same can be reduced. Since the damper operates by the utilization of the viscous resistance of the fluid having high viscosity extremely less changeable of viscosity due to temperature, a constant and extremely stable damper function can be achieved even if the temperature varies.
  • a piston is fitted to be rotatable in a case fitted to the valve body so as to form an annular space between the case and the piston, the high viscosity fluid is sealed up in the annular space to make large a rotational resistance of the piston and the piston and the rotational shaft are coupled together so as to be rotated together.
  • the lever may be mounted to the piston and the arm may be attached to the rotational shaft.
  • the piston and the rotational shaft may be coupled by engaging the pin provided for the arm with the cutout groove formed to the lever.
  • a piston is fitted in a case fitted rotatably in the valve body to form an annular space between the case and the piston, the high viscosity fluid is sealed up in the annular space to increase a rotational resistance of the case, and the case and the operation member are coupled with each other so as to rotate both the case and the operation member together.
  • a projection may be formed to the case, a recessed groove may be formed to the operation member, and the case and the operation member are coupled through the engagement between the recessed groove and the projection.
  • the damper has another structure in which a pair of pistons coupled together are secured in the valve body, cylinders are fitted to the pistons to be slidable to form cylinder chambers between the pistons, the high viscosity fluid is sealed up in the cylinder chambers to increase a sliding resistance of the cylinders, and the cylinders and the rotational shaft are coupled with each other so as to slide the cylinders in relation to a rotation of the rotational shaft.
  • an arm is attached to the rotational shaft, flange portions are formed to the cylinders, and the rotational shaft and the cylinders are coupled through the arm abutting against the flange portions.
  • Fig. 1 is a front view of a hydraulic pilot valve including a first embodiment of a damper according to the present invention.
  • Fig. 2 is a sectional view taken along the line II-II of Fig. 1.
  • Fig. 3 is a sectional view taken along the line III-III of Fig. 1.
  • Fig. 4 is a sectional view of a hydraulic pilot valve including a second embodiment of a damper according to the present invention.
  • Fig. 5 is a sectional view taken along the line V-V of Fig. 4.
  • Fig. 6 is a sectional view of a hydraulic pilot valve including a third embodiment of a damper according to the present invention.
  • Fig. 7 is a sectional view taken along the line VII-VII of Fig. 6.
  • Figs. 1 to 3 show a hydraulic pilot valve provided with a damper according to the first embodiment of the present invention.
  • a valve body 4 is composed of a lower body 1, a plate 3 attached to the lower body 1 and an upper body 2 mounted further on the plate 3.
  • An axial bore 5 is formed to the upper body 2 so as to extend in a horizontal direction, and a pair of rotational shafts 6 are inserted into the bore 5 and supported thereby through a bush7to be rotatable.
  • Operation members 8 are mounted to the rotational shafts 6, respectively, and as shown in Fig. 3, four pressure reducing valves 9 are disposed to the lower body 1 so as to face both ends of the respective operation members 8.
  • Each of the pressure reducing valves 9 comprises, as shown in Fig. 3, a spool 12 communicating or shutting out an inlet port 10 and an outlet port 11, a retainer 13 engaged with an upper end portion of the spool 12, a spring 16 for urging the retainer 13 against the upper end portion of the spool 12, a main spring 14 for urging upward the spool 12 through the retainer 13 to a shut-out position, and a piston 15 fitted in the spool 12 from an upper side thereof.
  • the piston 15 When the piston 15 is pushed downward by the operation members 8, the spool 12 moves towards the communication position to thereby establish the communication between the inlet port 10 and the outlet port 11 to thereby deliver the hydraulic oil from the inlet port 10 to the outlet port 11.
  • the lower body 1 has, as shown in Fig. 2, a recessed portion 1a having an upward opening to which a rotational damper 20 is mounted.
  • a case 21 having an axial bore 21a is fitted in the upward recessed portion la of the lower body 1, and a pair of pistons 22 are fitted in the axial bore 21a to be rotatable in a manner opposing to each other so that the pistons 22 are not removed from the axial bore 21a by means of snap rings 23 and press plates 24.
  • Each of the pistons 22 is formed with a small diameter portion 22a to provide an annular space 25 having a distance of about 0.1 to 0.15mm between the small diameter portion 22a and the axial bore 21a of the case 21, and a fluid having a high viscosity such as silicon oil is supplied into the annular space 25 through an oil hole 26 formed to the piston 22 and a sealing condition for the fluid is established by means of a sealing member.
  • a plug 27 is applied to the oil bore 26 of the piston 22.
  • the piston 22 has a small diameter portion 22b projecting over the case 21 to which a lever 28 having a cutout groove 31 is secured, and a pin 30 provided for an arm 29 fastened by a bolt to the end portion of each of the rotational shafts 6 is fitted to the cutout groove 31 of the lever 28, thereby rotating the pistons 22 in accordance with the rotation of the rotational shafts 6.
  • case 21 may be formed integrally with the lower body 1 or the plate 3, or formed as separate members which are to be fastened by means of bolts.
  • This embodiment will operates in the following manner.
  • the piston 22 is also rotated together with the rotational shafts 6, and the piston 22 is subjected at this time to the viscous resistance by the fluid having high viscosity sealed up in the annular space 25, so that the rotational resistance becomes large, thus attaining the damper function.
  • Figs. 4 and 5 show a hydraulic pilot valve including the second embodiment of the present invention.
  • This embodiment differs from the first embodiment in that the piston 22 of the damper 20 is formed of an elongated integral body, both end portions of the piston 22 are fixed to the plate 3 through brackets 33, a pair of cylindrical cases 21 are fitted to the piston 22 to be rotatable so that an annular space 25, in which a fluid having high viscosity fills, is formed between the cases 21 and the piston 22, and projections 34 formed integrally to the outer peripheral surfaces of the cases 21 are fitted to a recessed groove 35 formed to the operation member 8.
  • the rotational damper 20 of the first embodiment may be constructed such that the bush 7 and the rotational shafts 6 are instead composed of the case 21 and the piston 22, respectively, and the annular space in which the high viscosity fluid is sealed up is formed between the bush 7 and the rotational shafts 6. In such case, it is of course not necessary to locate any connection structure between the damper and the rotational shafts or operation member.
  • Figs. 6 and 7 show a hydraulic pilot valve including the third embodiment of the present invention, in which a direct-drive-type damper 40 is mounted to the lower body 1.
  • the direct-drive-type damper 40 has a structure such that a pair of pistons 43 are coupled together through a connection rod 45 and fixed to the lower body 1 by a pair of bolts 46 so as to clamp the same, cylinders 41 are fitted to the paired pistons 43, respectively, to be slidable such that a cylinder chamber 44 is formed between the respective pistons 43 and cylinders 41, and a fluid having high viscosity is sealed up in the cylinder chamber 44 to thereby increase the sliding resistance of the cylinders 41.
  • a pair of flange portions 48 are formed to the central portions of the outer peripheral surfaces of the respective cylinders 41, and a circular portion formed to the front end of an arm 47 attached to the rotational shaft 6 is fitted between the paired flange portions 48 so that both end surfaces 47a of the circular front end portion abuts against the paired flange portions 48 of the cylinders 41.
  • the damper for applying the operational resistance to the operation member 8 is disposed in the valve body, the hydraulic pilot valve is itself made compact and a space for setting the valve can be reduced. Furthermore, the damper utilizes the viscous resistance of the high viscosity fluid, the damper function is made constant even if a temperature of the fluid varies, thus achieving a stable damper function.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanically-Actuated Valves (AREA)
  • Servomotors (AREA)

Claims (7)

  1. Hydraulisches Pilotventil mit einer Vielzahl von Druckreduzierventilen (9), einer Rotationswelle (6), einem an der Rotationswelle (6) angebrachten Betriebselement (8), einem Bedienelement (32), welches die Rotationswelle (6) in Drehung versetzt, und einem Ventilgehäuse (1, 2), wobei die Druckreduzierventile (9) durch das Betriebselement (8) in Betrieb gesetzt werden, indem die Rotationswelle (6) mit Hilfe des Bedienelements (32) in Drehung versetzt wird, und ein mit dem Betriebselement (8) verbundenes Dämpfungselement geschaffen wird,
    dadurch gekennzeichnet, dass
    das Dämpfungselement im Ventilgehäuse (1, 2) angeordnet ist und einen Zwischenraum (25) aufweist, welcher eine hochviskose Flüssigkeit enthält, und zwei Elemente (22, 21; 41, 45) des Dämpfungselementes benachbart zu dem Zwischenraum (25) vorhanden sind, die sich als Reaktion auf die Bewegung des Betriebselements (8) zueinander bewegen lassen, wodurch auf das Betriebselement (8) ein Betriebswiderstand einwirkt, der durch den Viskositätswiderstand der Flüssigkeit verursacht wird, und wodurch das Volumen des Zwischenraums weitgehend konstant bleibt, während sich die beiden Elemente zueinander bewegen.
  2. Hydraulisches Pilotventil nach Anspruch 1, wobei ein Kolben (22) drehbar in einem am Ventilgehäuse (1, 2) befestigten Mantel (21) untergebracht ist, so dass der ringförmige Zwischenraum (25) zwischen dem Mantel (21) und dem Kolben (22) entsteht, die hochviskose Flüssigkeit zur Vergrößerung eines Rotationswiderstandes des Kolbens (22) in dem ringförmigen Zwischenraum (25) eingeschlossen wird und der Kolben (22) und die Rotationswelle (6) miteinander verbunden sind, damit sie sich zusammen drehen.
  3. Hydraulisches Pilotventil nach Anspruch 1 oder 2, wobei ein Hebel (28) an dem Kolben (22) angebracht ist, an der Rotationswelle (6) ein Arm (29) angebaut ist, und der Kolben (22) und die Rotationswelle (6) miteinander verbunden sind, indem ein am Arm (29) ausgebildeter Stift (30) mit einer Kerbe (31) am Hebel (28) in Eingriff kommt.
  4. Hydraulisches Pilotventil nach Anspruch 1, wobei ein Kolben (22) in einem Mantel (21) untergebracht ist, welcher drehbar in dem Ventilgehäuse (1, 2) befestigt ist, so dass ein ringförmiger Zwischenraum (25) zwischen dem Mantel (21) und dem Kolben (22) entsteht, die hochviskose Flüssigkeit zur Vergrößerung eines Rotationswiderstandes des Mantels (21) in dem ringförmigen Zwischenraum (25) eingeschlossen wird und der Mantel (21) und das Betriebselement (8) miteinander verbunden sind, damit sie sich zusammen drehen.
  5. Hydraulisches Pilotventil nach Anspruch 4, wobei an dem Mantel (21) ein Vorsprung (34) ausgebildet ist, an dem Betriebselement (8) eine Kerbe (35) ausgebildet ist und der Mantel (21) und das Betriebselement (8) durch den Eingriff zwischen der Kerbe (35) und dem Vorsprung (34) miteinander verbunden sind.
  6. Hydraulisches Pilotventil nach Anspruch 1, wobei ein untereinander verbundenes Kolbenpaar (43) in dem Ventilgehäuse (1, 2) untergebracht ist, an den Kolben (43) Zylinder (41) derart angebracht sind, dass sie sich gleitend bewegen können und so zwischen den Kolben (43) eine Zylinderkammer (44) schaffen, in der zur Erhöhung des Gleitwiderstands der Zylinder die hochviskose Flüssigkeit eingeschlossen wird, und die Zylinder (41) und die Rotationswelle (6) so miteinander verbunden sind, dass sich die Zylinder (41) gleitend zu der Rotationswelle (6) bewegen.
  7. Hydraulisches Pilotventil nach Anspruch 6, wobei an der Rotationswelle (6) ein Arm (47) angebracht ist, an den Zylindern (41) Flanschabschnitte (48) ausgebildet sind und die Rotationswelle (6) und die Zylinder (41) über den Arm (47), der an die Flanschabschnitte (48) anstößt, miteinander verbunden sind.
EP94927797A 1993-09-28 1994-09-28 Dämpfer für ein hydraulisches pilotventil Expired - Lifetime EP0753668B1 (de)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP241058/93 1993-09-28
JP24105893A JP3503756B2 (ja) 1993-09-28 1993-09-28 油圧パイロット弁のダンパ装置
JP24105893 1993-09-28
PCT/JP1994/001606 WO1995009306A1 (fr) 1993-09-28 1994-09-28 Amortisseur pour servo-soupape hydraulique

Publications (3)

Publication Number Publication Date
EP0753668A1 EP0753668A1 (de) 1997-01-15
EP0753668A4 EP0753668A4 (de) 1998-02-11
EP0753668B1 true EP0753668B1 (de) 2001-02-21

Family

ID=17068686

Family Applications (1)

Application Number Title Priority Date Filing Date
EP94927797A Expired - Lifetime EP0753668B1 (de) 1993-09-28 1994-09-28 Dämpfer für ein hydraulisches pilotventil

Country Status (6)

Country Link
US (2) US5845680A (de)
EP (1) EP0753668B1 (de)
JP (1) JP3503756B2 (de)
KR (1) KR0177290B1 (de)
DE (1) DE69426729T2 (de)
WO (1) WO1995009306A1 (de)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3503756B2 (ja) * 1993-09-28 2004-03-08 株式会社小松製作所 油圧パイロット弁のダンパ装置
WO2005033823A1 (ja) * 2003-09-30 2005-04-14 Komatsu Ltd. 操作レバー装置
FR2938309B1 (fr) * 2008-11-12 2010-10-29 Bosch Rexroth Dsi Sas Dispositif de regulation de pression, notamment du type telecommande hydraulique

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6111551Y2 (de) * 1980-09-30 1986-04-11
JPS5761247A (en) * 1980-09-30 1982-04-13 Toshiba Corp Yoke assembly for image pickup tube
JPS58176169A (ja) * 1982-04-08 1983-10-15 樋　幸四郎 廃棄物焼却灰および産業廃棄物クリンカ−の焼成溶融結合による煉瓦材料とその製法
JPS58176169U (ja) * 1982-05-19 1983-11-25 日立建機株式会社 手動切換弁の操作装置
JPH07103942B2 (ja) * 1988-03-31 1995-11-08 株式会社小松製作所 油圧パイロットバルブ装置
JPH03105787A (ja) * 1989-09-19 1991-05-02 Nec Ic Microcomput Syst Ltd 半導体集積回路
JPH03249414A (ja) * 1990-02-27 1991-11-07 Komatsu Ltd 油圧パイロット弁
JPH0724485B2 (ja) * 1990-05-30 1995-03-22 財団法人北海道農業開発公社 籾殻投入心土改良耕工法並びに該工法用作業機
JPH0453853A (ja) * 1990-06-22 1992-02-21 Mitsui Toatsu Chem Inc 新規な熱可塑性樹脂組成物
WO1994009278A1 (en) * 1992-10-09 1994-04-28 Kabushiki Kaisha Komatsu Seisakusho Hydraulic pilot valve
JP3503756B2 (ja) * 1993-09-28 2004-03-08 株式会社小松製作所 油圧パイロット弁のダンパ装置

Also Published As

Publication number Publication date
US5845680A (en) 1998-12-08
WO1995009306A1 (fr) 1995-04-06
EP0753668A1 (de) 1997-01-15
US5983942A (en) 1999-11-16
JP3503756B2 (ja) 2004-03-08
DE69426729T2 (de) 2001-06-07
JPH0791407A (ja) 1995-04-04
KR0177290B1 (ko) 1999-04-15
KR960705144A (ko) 1996-10-09
DE69426729D1 (de) 2001-03-29
EP0753668A4 (de) 1998-02-11

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